body {
    overflow: hidden;
}
/*后浪推前浪：后面的样式覆盖前面的，各自也保留各自独特的样式*/
body > .page {
    display: flex;
    flex-wrap: wrap;
}

body > .page > section {
    width: 50vw;
    height: 50vh;
    border: 1px solid cornflowerblue;
}